Normally, to measure a blood pressure value, a cuff provided with a fluid bag for pressing an artery located within a living body is wound around the body surface, and arterial pressure pulse waves caused in the artery by inflation/deflation of the fluid bag are detected to measure the blood pressure value. Here, the cuff refers to a band-shaped structure having a bladder, which can be wound around a part of a living body, for use in measurement of arterial pressure of an upper limb, a lower limb or the like by introducing fluid such as gas or liquid into the bladder. Thus, the cuff represents the concept including the fluid bag as well as members for winding the fluid bag around the living body. Particularly, the cuff wound around and applied to a wrist or an upper arm is also called an arm band or a manchette.
The cuff for a blood pressure monitor has a bag-shaped cover body containing an air bag as a fluid bag therein. The bag-shaped cover body is usually formed into a bag shape by stacking two sheet-shaped members constituting an inner cover member and an outer cover member one on the other and connecting their rims. The cuff for a blood pressure monitor having such a configuration is disclosed, e.g., in Japanese Patent Laying-Open Nos. 09-117419 (Patent Document 1) and 09-238910 (Patent Document 2).
In recent years, it is common to provide the cuff for a blood pressure monitor with a curled elastic member, identified as an elastic member, within the bag-shaped cover body and on the outer side of the air bag, so as to facilitate the operation of applying the cuff by the subject and also to allow the air bag to expand smoothly toward the living body at the time of pressurizing the air bag after application of the cuff (see, e.g., Patent Documents 1 and 2 described above and Japanese Patent Laying-Open No. 2002-209858 (Patent Document 3)). As the curled elastic member, a plate-like member made of resin, which is wound annularly and elastically deformable in a radial direction, may be used.    Patent Document 1: Japanese Patent Laying-Open No. 09-117419    Patent Document 2: Japanese Patent Laying-Open No. 09-238910    Patent Document 3: Japanese Patent Laying-Open No. 2002-209858